Jet engine technology boosts LED output

General Electric
Co.’s product mix runs from jet engines to lightbulbs. Now one is benefiting
from the other, after scientists combined jet engine cooling technology with LED
bulbs.

The researchers, from GE’s Global Research and Lighting
divisions and the University of Maryland in College Park, have developed a 1500-lm
LED bulb as part of a two-year solid-state lighting program with the US Department
of Energy; they say it addresses obstacles to more widespread adoption of these
bulbs for general lighting.

Mehmet Arik, a mechanical engineer
at GE Global Research and principal investigator on the LED project, displays GE’s
new LED. Courtesy of General Electric Co.
With the new cooling technology, the number of LED chips required
to generate 1500 lm of light is just a fraction of that required for today’s
LED lamps, which produce less than half of the light output. With a more effective
cooling solution, GE says that the chips can be run harder to produce more light.

“GE’s cooling solution is based on technology the
company now uses in its aviation and energy businesses,” said Todd E. Alhart,
a spokesman for GE Global Research, which has a team of fluidics experts that specializes
in flow management technologies. “[The team is] developing innovative ways
to control airflow and combustion to dramatically reduce the amount of pressure
losses and loading characteristics in aircraft engines, and power generation in
gas and wind turbines.”

GE dual cool jets are very small micro-fluidic devices, much like
bellows that provide high-velocity jets of air that impinge on the LED heat sink
and increase the heat transfer rate to more than 10 times that of natural convection.

For a given lumen output, the improved thermal management from
the dual cool jets reduces the necessary LED chip count, which can significantly
lower the cost of the lamp, according to GE. The cooling technology also makes it
possible to reduce LED lamp size and weight.

“The cooling process we have developed was demonstrated
in a prototype LED downlight, but we really see this as a technology platform that
could benefit several LED lighting products in the future,” Alhart noted. “More
development is required in the months ahead to prove the life and reliability and
miniaturize the size of the jets to work in small form factors. When ready, we will
work with the [GE] Lighting business on commercialization plans.

“As mentioned, the project we have been working on is really
driving a broader technology platform that could support several LED lighting products
in the future. We still have some work in the lab to complete in the months ahead
before moving forward with commercialization plans. But we envision a technology
platform that could benefit several commercial LED lighting products. That will
be something our Lighting business will determine when ready.